Toggle press

ABSTRACT

A toggle press including a pair of coextensive spaced apart side plates having a stationary die jaw mounted therebetween. A movable die jaw is disposed adjacent the stationary die jaw and is formed on one side with a first bearing surface. A toggle link is engaged on one end with the movable jaw and on the opposite end with a lever arm mounted to the side plate by means of a pivot mount. Floating bearings are interposed between the opposite ends of the link and the lever arm and movable die, respectively. The toggle link is arranged such that rotation of the lever arm to close the movable die jaw on the stationary die jaw causes such link to be brought into longitudinal alignment between the end thereof engaging the movable die and the lever arm pivot mount to thereby provide a high torque on such link as the die jaws are closed while applying only compressive forces to the bearings.

[ TOGGLE PRESS [76] Inventor: Frank E. Shaffer, 113 B Clearbrook Ln., Costa Mesa, Calif. 92626 [22] Filed: May 7, 1973 [21] App]. No.: 357,885 1 Related US. Application Data [63] Continuation-impart of Ser. No. 204,153, Dec. 2,

1971, abandoned.

[52] US. Cl 72/451 72/416, 72/470, 100/271 [51] Int. Cl B2lj 9/18 [58] Field of Search 72/451, 450, 453, 412, 72/415, 416, 470, 410; 100/271 [56] References Cited UNITED STATES PATENTS 800,508 9/1905 Stambaugh 72/453 2,162,133 6/1939 Spire 100/271 3,472,057 10/1969 Persieo 72/450 3,552,183 1/1971 Heitmann 100/271 3,577,591 4/1971 Ricards 100/271 [451 Oct. 22, 1974 Primary Examiner-Charles W. Lanham Assistant Examiner-Gene P. Crosby Attorney, Agent, or Firm-Fu1wider, Patton, Rieber, Lee & Utecht 5 7] ABSTRACT A toggle press including a pair of coextensive spaced apart side plates having a stationary die jaw mounted therebetween. A movable die jaw is disposed adjacent the stationary die jaw and is formed on one side with a first bearing surface. A toggle link is engaged on one end with the movable jaw and on the opposite end with a lever arm mounted to the side plate by means of a pivot mount. Floating bearings are interposed between the opposite ends of the link and the lever arm and movable die, respectively. The toggle link is arranged such that rotation of the lever arm to close the movable die jaw on the stationary die jaw causes such link to be brought into longitudinal alignment between the end thereof engaging the movable die and the lever arm pivot mount to thereby provide a high torque on such link as the die jaws are closed while applying only compressive forces to the bearings.

11 Claims, 7 Drawing Figures 1 TOGGLE PRESS CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation-impart of US. Ser. No. 204,153, filed Dec. 2, 1971 and now abandoned.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to presses of the type that may be used in swaging sleeves on tables and other punching and forming operations.

2. Description of the Prior Art Numerous swaging and forming devices have been proposed but such devices generally require an extremely massive frame and bearing arrangements to withstand the forces developed during repeated operation thereof and also require high driving forces in order to develop the necessary pressure to accomplish the forming operations. Devices of this type are shown in U.S. Pat. Nos. 3,552,183 and 3,577,591.

SUMMARY OF THE INVENTION The toggle press of present invention is characterized by a toggle link for controlling movement of a movable die jaw. One end of the toggle link engages the movable jaw and the opposite end of such link is controlled by a pivotable lever arm. Floating bearings are interposed between the opposite ends of the link and the movable jaw and lever arm, respectively. The link is of sufficient length to cause such link to be brought into longitudinal alignment between the pivot mount of the lever arm and the contact point with the movable die as the die jaws are closed to create a high torque on such link during final closing movement of the jaws to create high operative forces on such jaws.

DESCRIPTION OF THE DRAWINGS FIG. 6 is a vertical sectional view similar to FIG. but showing the press in the die-closed position; and

FIG. 7 is an end view of the toggle press shown in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 and 3, the toggle press of the present invention includes a frame formed by a pair of side plates 13 and 15 which are spaced apart to form a compartment for receipt of stationary and movable die jaws I7 and 19 which mount respective stationary and movable dies 21 and 23. A vertically extending toggle link 25 controls movement of the movable jaw 19 and is engaged on its upper end with the overhang of a lever arm 27 that is pivotally mounted to the side plates 13 and 15 by means of a pair of aligned pivot pins 29. Floating bearings 73 and 79 are interposed between the opposite ends of the link 25 and the arm 27 and the movable die 19to be placed in compression upon actuation of the press. The arrangement of the link 25 and arm 27 is such that as the jaws l7 and 19 close, the link 25 assumes the vertical position shown in FIG. 4, thereby causing the lever arm 27 to exert a relatively large clockwise torque on such link 25 to apply high operative forces to the dies 21 and 23.

The side plates 13 and 15 are conveniently made from /;-inch thick plate material and are formed inthe lower portion of their front edges with respective cutouts 33 and 35 disposed in transverse alignment with the dies 21 and 23 for passage of work pieces. The dies 21 and 23 include confronting semicylindrical cavities 34 and 36 for receipt of work pieces. Reinforcing plates 100 are mounted on the exterior of the frame plates 13 and 15 by means of a bolt assembly 101, such bolthaving a spacing sleeve 102 telescoped over the shank thereof and disposed between the plates 13 and 15.

Referring to FIGS. 3 and 4, a backing plate 37 is mounted on thestationary jaw 17 and has the stationary die 21 abutted against the front end thereof. The stationary die 21 is formed with a rearwardly projecting bore 41 which receives a mounting screw 43 that projects therethrough and screws into a threaded bore 45 formed in the backing plate 37.

The pivot pins 29 are in the form of stub pins press fit into bores formed in the reinforcing plates 100 and frame plates 13 and 15 and projecting therefrom into a bore in the handle 27, such pins terminating in spaced apart pins defining therebetween a lubricant-receiving cavity having an oil-soaked piece of felt 103 disposed therein.

The movable jaw 19 is carried from a movable support plate 47 which is pivotally mounted on a transverse pivot pin 49 and has the movable die 23 abutted against the front end thereof. Referring to FIG. 4, the movable die 23 is also formed with a rearwardly projecting through bore 51 for receipt of a mounting screw 53 that projects therethrough and screws into a threaded bore 55 formed in the support plate 47. The movable jaw 19 includes a downwardly projecting through bore 57 which receives a screw 59 that is screwed into a threaded bore 61 formed in the mounting plate 47. Sandwiched between the movable jaw 19 and mounting plate 47 is a plurality of shims 63 for maintaining the die 23 the stationary die 21.

Referring to FIG. 4, the backing plate 37 and mounting plate 47 are formed with confronting bores 55 which receive opposite ends of a coil spring 67 that jaw 19 to the open posi normally biases the movable tion shown in FIG. 3.

The upper side of the free extremity of the movable jaw 19 is formed with a transversely extending semicylindrical bearing socket 71 which receives one side of a transversely extending bearing rod 73. The lower extremity of the toggle link 25 is also formed with a transversely extending semicylindrical bearing socket 75 for receipt of the opposite side of such bearing rod 73. The upper extremity of the toggle link 25 is likewise formed with a transversely extending semicylindrical socket 77 which receives one side of a bearing rod 79, the opposite side of such bearing rod 79 being received in a transversely extending semicylindrical socket 81 formed in the overhang 83 of the lever arm 27.

properly spaced with respect to stop pins 85 and 87 extend between the plates 13 and 15 for limiting upward travel of the movable jaw 19 and downward travel of the free extremity of the lever arm 27, respectively. Also, a stop pin 102 limits rearward travel of the upper extremity of the toggle link 25 as shown in FIG. 4 to prevent such toggle link from going over center and locking the jaws 19 and 21 in their closed position.

Referring to FIG. 1, the free end of the lever arm 27 is connected with an air cylinder 95 that has air thereto controlled by means of a foot-operated air control 97.

In operation, the toggle press of present invention may be either hand actuated or actuated by the air control cylinder 95. The fitting to be swaged is positioned in the stationary die cavity 34 and the foot control 97 depressed to actuate the cylinder 95 and drive the free end of the lever arm 27 upwardly to rotate such arm clockwise about the pivot pin 29 as viewed in FIG. 3. Clockwise rotation of the lever arm 27 rotates the overhang 83 downwardly and rearwardly to drive the toggle link 25 downwardly thereby pushing the movable jaw 19 downwardly toward its closed position. As the dies 21 and 23 close on the work piece (not shown), the toggle link 25 is brought into vertical alignment between the lower roller bearings 73 and lever arm pivot pin 29 thereby resulting in the majority of the force component on the upper portion of such link acting transversely of such link thereby creating a great torque on such link which drives the link downwardly with great force to-thereby press the movable die 23 against the lower die 21 with a relatively high force. Consequently, it will be appreciated that only a relatively small force may be applied to the handle 27 to create a large swaging force on the work piece. However, continued clockwise rotation of the handle 27 is stopped by means of the upper end of the toggle link 25 engaging the stop pin 102 to thereby prevent such toggle link from rotating beyond its position in alignment between the lower socket 71 and lever arm pivot pin 29 to thereby avoid the entire toggle linkage be coming locked up in over-the-center type action.

It will be appreciated that the bearing rollers 73 and 79 experience only compressive forces and are not subjected to any bending forces normally associated with prior art linkages of this type which incorporate through pivot pins carried from the frame walls. Conse- I quently, the entire fatiguing and wearing problems normally associated with such through pins is avoided thereby markedly lengthening the trouble free life of the toggle press of the present invention. Further the stub pivot pins 29 are only subjected to shearing and bending forces at the interface between the opposite sides of the handle 27 and interior surfaces of the respective frame plates 13 and 15 (FIG. 2) thus eliminating the normal bending stress applied to the central portion of a continuous through pivot pin as disclosed in prior art linkages.

Release of the foot control 97 enables the air cylinder 95 to retract thereby pivoting the control arm 27 counterclockwise and enabling the bias spring 67 to urge the free end of the movable jaw 19 upwardly to open the dies 21 and 23 for removal of the work piece (not shown).

The dies 21 and 23 may be conveniently changed by unscrewing the screws 43 and 53 and removing such dies 21 and 23 for replacement by dies of different sizes or for different functions, such as punching'operations.

Since the overall adjustment of the togglelinka'ge is critical to proper operation, the shims 63 are important to enable the spacing of the dies 21 and 23 to be maintained for appropriate operation of the press to enable the toggle link 25 to assume its vertical position as closure travel of the dies is completed. By utilizing a lever arm 27 of approximately 30 inches and a link 25 of approximately 3 inches, it has been determined that a press closing force of l0,000 pounds may be obtained. A press constructed in accordance with the preferred embodiment has been actuated in excess of 5,000 cycles and still shows no substantial wear and continues to operate very well.

The toggle press shown in FIGS. 5 through 7 is similar to that shown in FIG. 1 and includes a frame formed by a pair of side plates 12] and 123 having a stationary die 125 mounted at the lower extremity thereof with a movable die 127 being disposed thereover and mounted on one end from the side plates 121 and 123 by means of a pivot pin 129. The top side of the movable side 127 is formed with an upwardly facing semicylindrically shaped bearing socket 131. Disposed in alignment over the bearing socket 131 and spaced thereabove is a backing plate 135 having a downwardly and rearwardly facing semicylindrically bearing socket 137 formed in the lower extremity thereof. An elongated toggle link 139 projects upwardly from the jaw bearing socket 131 and is formed in its opposite extremitie's with cylindrically shaped bearing sockets 141 and 143, acylindrical roller bearing being received between the jaw bearing surface 131and the toggle bearing socket 141.

A pin 142 (FIGS. 5 and 6) projects between the plates 121 and 123 and has a carrier tube 144 telescoped thereover and a lever arm 146 is formed with a tip which projects between such pin and the backing plate bearing socket 137, such tip being formed in its rear extremity with a downwardly facing concave transversely extending indentation 147 which nests on the carrier roller 149 when the handle is in the retracted position shown in FIG. 5. The formed tip then curves generally downwardly and forwardly from the indentation 147 to form a convex actuating cam run 151. The lever arm 146 then projects beyond the actuating run 151 to be formed with a downwardly facing semicylindrical bearing socket 153 confronting the upwardly opening toggle socket 143. A cylindrical roller bearing 155 is interposed between such socket 153 and the toggle bearing socket 143. The extreme tip of the arm 146 then turns back on itself and is formed with an upwardly facing backing plate bearing socket 159 confronting the backing plate socket 137 and having a roller bearing 161 disposed therein.

Referring to FIG. 6, a threaded rod 167 is screwed through a tapped bore in the backing plate 135 to project therefrom and act as a limit stop for the lever arm 146 as it reaches its full actuated position shown in FIG. 6. A locking nut is screwed into such rod for locking it in position. Still referring to FIG. 6, an oil lubrication bore 171 is formed in the backing plate 135 for lubricating the bearing 161 and a similar bore 173 is formed in the tip of the arm 146 for receiving lubricant to maintain the bearings 161 and 155 lubricated.

A lubrication bore 176 extends the full length of the toggle link- 139 for receiving further lubrication. The toggle link 139 is held in position between the movable cam 127 and the actuating arm 146 by means of an L- shaped leaf spring 178 secured to the cam 127 by means of a mounting screw 180 and a formed leaf spring 182 secured to the toggle link by means of a mounting screw 184 and formed to curve around the projecting extremity of the lever arm 146 for engagement therewith.

The toggle press shown in FIGS. 5 through 7 operates similar to the toggle press shown in FIG. 1, it being appreciated that when the arm 146 is rotated to its full counterclockwise position with the depression 147 nested on the carrier roller 149, the bearing socket 153 will be rotated to its full counterclockwise position with respect to the bearing 161 thus pivoting the upper end of the toggle link 139 to the right enabling the free end of the movable jaw 127 to be raised upwardly by the biasing spring 130. After the part to be swaged is positioned between the jaws 125 and 127, the arm 146 may be rotated clockwise about the bearing 161 to the position shown in FIG. 6 thus causing the handle riser 151 to slide upwardly on the support roller 149 and causing the bearing 155 to be rotated counterclockwise with respect to the bearing 161 thereby carrying the upper extremity of the toggle link 139 to the left thereby aligning such link 139 longitudinally between the backing plate bearing 161 and the jaw bearing 145 thereby gaining the mechanical advantage normally associated with a toggle action.

As discussed hereinabove with respect to the toggle press shown in FIG. 1, it is important that the entire rotational action of the toggle linkage takes place about the bearings 161, 155 and 145 while maintaining such bearings in compression only and without applying any bending moments to such bearings. Experience has proven that in this arrangement, the bearings, toggle link and actuating lever arm will operate for many re peated cycles without overheating or excessive wear. However, in the prior art devices and even to some degree with the stub pins 29 incorporated in the toggle press shown in FIG. 1, the bending moments applied to such pins results in excessive heating, fatigue and wear, thus rapidly deteriorating the toggle press. This shortcoming makes itself evident by overheating of the bearings and consequent burning of the lubricant.

From the foregoing it will be apparent that the toggle press of present invention provides an economical and convenient means for swaging or pressing work pieces with relatively small driving forces.

Various modifications and changes may be made with regard to the foregoing detailed description with out departing from the spirit of the invention.

I claim:

1. A light weight high pressure toggle press comprising:

a frame;

relatively stationary die jaw means mounted on said frame;

movable die jaw means carried from said frame for movement from a closed position adjacent said stationary die means to an open position spaced from said stationary die jaw means and formed on its side opposite said stationary jaw means with a first bearing surface;

a lever arm formed with a second bearing surface;

pivot means pivotally carrying said lever from said frame;

a toggle link projecting between said first and second bearing surfaces and formed on its opposite extremities with third and fourth bearing surfaces, confronting said respective first and second bearing surfaces; and

first and second floating bearings disposed between said respective first and third and said second and fourth bearing surfaces, said toggle link being of sufficient length to rotate said link upon rotation of said lever arm to cause said link to be moved into substantial alignment between said pivot means and said first bearing surface as said movable jaw is shifted to its closed position to thereby provide a high mechanical advantage while applying only compressive forces to said bearing means.

2. A toggle press as set forth in claim 1 wherein:

said frame includes a pair of spaced apart plates formed with open-endedcut-outs aligned with said die jaws for receipt of articles to be swaged.

3. A toggle press as set forth in claim 2 that includes:

pivot means for mounting one end of said movable die jawto said plates. 4. A toggle press as set forth in claim 1 that includes:

removable dies;

means mounting said dies on said jaws for convenient removal.

5. A toggle press as set forth in claim 1 that includes:

bias means biasing said movable jaw to its open position. 6. A toggle press as set forth in claim 1 that includes:

fluid piston drive means connected with said lever arm for actuating said device.

7. A toggle press asset forth in claim 1 wherein:

said frame includes a pair of spaced apart plate means projecting on opposite sides of said lever arm;

said lever arm includes a through transverse bore;

and

said pivot means includes a pair of stub pinscarried from said respective plate means and projecting into opposite ends of said bore.

8. A toggle press as set forth in claim 1 wherein:

said bearing surfaces are semi-cylindrically shaped and said bearings are formed with ,complemental cylindrical shapes. 9. A toggle press as set forth in claim 7 that includes:

0nd bearing surfaces; and

first and second floating bearings disposed between said first and third bearing surfaces and between said second and fourth bearing surfaces for carrying compressive forces applied to said toggle link, said toggle link being of suffieient length to be moved into alignment between said first bearing surface and said pivot means thereby providing a high mechanical advantage while applying only compressive forces to said bearing means. 

1. A light weight high pressure toggle press comprising: a frame; relatively stationary die jaw means mounted on said frame; movable die jaw means carried from said frame for movement from a closed position adjacent said stationary die means to an open position spaced from said stationary die jaw means and formed on its side opposite said stationary jaw means with a first bearing surface; a lever arm formed with a second bearing surface; pivot means pivotally carrying said lever from said frame; a toggle link projecting between said first and second bearing surfaces and formed on its opposite extremities with third and fourth bearing surfaces, confronting said respective first and second bearing surfaces; and first and second floating bearings disposed between said respective first and third and said second and fourth bearing surfaces, said toggle link being of sufficient length to rotate said link upon rotation of said lever arm to cause said link to be moved into substantial alignment between said pivot means and said first bearing surface as said movable jaw is shifted to its closed position to thereby provide a high mechanical advantage while applying only compressive forces to said bearing means.
 2. A toggle press as set forth in claim 1 wherein: said frame includes a pair of spaced apart plates formed with open-ended cut-outs aligned with said die jaws for receipt of articles to be swaged.
 3. A toggle press as set forth in claim 2 that includes: pivot means for mounting one end of said movable die jaw to said plates.
 4. A toggle press as set forth in claim 1 that includes: removable dies; means mounting said dies on said jaws for convenient removal.
 5. A toggle press as set forth in claim 1 that includes: bias means biasing said movable jaw to its open position.
 6. A toggle press as set forth in claim 1 that includes: fluid piston drive means connected with said lever arm for actuating said device.
 7. A toggle press as set forth in claim 1 wherein: said frame includes a pair of spaced apart plate means projecting on opposite sides of said lever arm; said lever arm includes a through transverse bore; and said pivot means includes a pair of stub pins carried from said respective plate means and projecting into opposite ends of said bore.
 8. A toggle press as set forth in claim 1 wherein: said bearing surfaces are semi-cylindrically shaped and said bearings are formed with complemental cylindrical shapes.
 9. A toggle press as set forth in claim 7 that includes: lubricAnt means interposed in said bore between said stub pins for lubricating said pins.
 10. A toggle press as set forth in claim 1 wherein: said pivot means includes backing plate means mounted on said frame spaced from said link, and formed with a fifth bearing surface facing generally toward said toggle link; one extremity of said lever arm is interposed between said link and fifth bearing surface and is formed with a sixth bearing surface confronting said fifth bearing surface; and said pivot means includes floating bearing means interposed between said fifth and sixth bearing surfaces.
 11. Force multiplying apparatus comprising: a frame; a driven member formed on one side with a first concave bearing surface; a lever arm formed with a second concave bearing surface facing said first bearing surface; pivot means spaced from said second bearing surface and carrying said lever arm from said frame; a toggle link projecting between said first and second bearing surfaces and formed on its opposite extremities with third and fourth concave bearing surfaces confronting said respective first and second bearing surfaces; and first and second floating bearings disposed between said first and third bearing surfaces and between said second and fourth bearing surfaces for carrying compressive forces applied to said toggle link, said toggle link being of sufficient length to be moved into alignment between said first bearing surface and said pivot means thereby providing a high mechanical advantage while applying only compressive forces to said bearing means. 